Chemical pollution is considered a factor that may threaten marine protected areas (MPAs). However, organized data on this topic are lacking.

This study reviewed the literature on pollution in MPAs in order to compile data, determine whether MPAs are influenced by pollution and, whenever possible, describe how they are being affected by contaminants.

The obtained results show that the pollution status is unknown in most MPAs worldwide. The authors state that when any information is available, it is often insufficient to diagnose the threats to biodiversity or to support further actions.

The review shows that more of the 80% of the areas studied exhibited evidence of contamination at potentially toxic concentrations or were found to have a status that produced toxic effects on the biota.

Taking into account the lack of information evidenced by this review, the authors encourage the scientific community to study pollution in MPAs worldwide.